Mycotoxins in Poultry

Abstract

Mycotoxins, the toxic secondary metabolites of fungi, particularly produced by many species of Aspergillus, Fusarium and Penicillium, have afected animal and human health for over thousand years, whereas litle has been discovered so far about these complex substances in poultry, which are generally very sensitive. Even though it varies by species and sex, some common efects are reduced feed intake, weight gain, feed eiciency, growth performance, immunity and hatchability along with increased mortality, organ damages (mainly kidney and liver), carcinogenicity, teratogenicity and decreased egg production. Besides their adverse health efects and the decrease in production rate, concerns over their importance in public health is still under debate. Decontamination approaches to reduce mycotoxins in feed are technologically diverse and based on chemical, biological and physical strategies. Chemical remediation strategies involve the conversion of mycotoxins via chemical reactions. Biological strategies involve various substances such as plant ingredients, enzymes and microorganisms. Physical processes include sorting, milling, dehulling, cleaning, heating, irradiation or combinational approaches. New strategies for the prevention and treatment of mycotoxicosis, including beneicial microorganisms/products, along with alternative treatments, including plant extracts/essential oils, are current hot topics in the poultry industry.

Effects of Season and House Microclimate on Fungal Flora in Air and Broiler Trachea

“…Potentially harmful fungi were identified in both seasons. Aspergillus flavus and A. niger are known to produce mycotoxins and can have a role in the outbreak of aspergillosis, A. flavus in particular [16,36]. Although Aspergillus sp., predominantly A. flavus, prevailed both in house air and in broiler trachea in summer, A. fumigatus and A. terreus were found in house air and in broiler trachea in winter.…”

Aflatoxins: Their Toxic Effect on Poultry and Recent Advances in Their Treatment

“…Cereals and their products are susceptible to fungal invasion that may be accompanied by mycotoxin production [17]. Approximately 25-40% of cereals produced worldwide are directly or indirectly contaminated with mycotoxins especially AFs with annual losses of around 1 billion MT of food products [9,18]. A. flavus and A. parasiticus are responsible for producing AF during storage particularly in hot and humid countries in the tropics as compared to those in the temperate regions of the world [9,19].…”

“…Due to recent advances in technology, modern methods and budding interests, more than 300-500 mycotoxins have been discovered and characterized. Mycotoxins have very special chemical configurations [11,18,34]. However, only a relatively small number of toxins are of relevance in feed milling [11].…”

“…AFs bind to both RNA and DNA and blocks transcription [17]. In the liver, cytochrome P450 activates AFB 1 (procarcinogens) to form AFB 1 -8, 9-exo-epoxide (catalyzed by CYP3A4 leading to the formation of AFQ 1 ) and endo-epoxide (catalyzed by CYP1A2) at 8, 9 position of the terminal furan ring and its subsequent covalent binding to nucleic acid but only exo-epoxide that is highly unstable binds with DNA resulting in the formation of 8,9-dihydro-8-(N7-guanyl)-9-hydro-AFB 1 (AFB 1 -N7-Gua) adduct [18,56,57]. Toxin interaction with DNA and some enzymes to alter p53 gene results in GC to TA transversion, which results in mutagenic properties.…”

“…Mycotoxins including Aflatoxins are metabolized in the gastrointestinal tract, liver or kidneys according to their chemical structure. Their transfer to poultry meat and eggs leads to undesirable effects on human health [18]. Agag [3] examined the "carry-over" of AFB 1 from layer feed to eggs was examined in laying hens at dietary levels of 100-400 μg/kg AFB1.…”